[PATCH v3 11/35] x86/bugs: Restructure spectre_v1 mitigation

David Kaplan
2025-01-08T20:25:48Z

Restructure spectre_v1 to use select/apply functions to create
consistent vulnerability handling.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
---
arch/x86/kernel/cpu/bugs.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 58ac99b74bd3..3d468bd9573f 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -54,6 +54,7 @@
*/

static void __init spectre_v1_select_mitigation(void);
+static void __init spectre_v1_apply_mitigation(void);
static void __init spectre_v2_select_mitigation(void);
static void __init retbleed_select_mitigation(void);
static void __init spectre_v2_user_select_mitigation(void);
@@ -216,6 +217,7 @@ void __init cpu_select_mitigations(void)
mmio_update_mitigation();
rfds_update_mitigation();

+ spectre_v1_apply_mitigation();
mds_apply_mitigation();
taa_apply_mitigation();
mmio_apply_mitigation();
@@ -1000,10 +1002,14 @@ static bool smap_works_speculatively(void)

static void __init spectre_v1_select_mitigation(void)
{
- if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1) || cpu_mitigations_off()) {
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1) || cpu_mitigations_off())
spectre_v1_mitigation = SPECTRE_V1_MITIGATION_NONE;
+}
+
+static void __init spectre_v1_apply_mitigation(void)
+{
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1) || cpu_mitigations_off())
return;
- }

if (spectre_v1_mitigation == SPECTRE_V1_MITIGATION_AUTO) {
/*
--
2.34.1